As is known, the terms “baling machine” or “forage press” are commonly used to indicate agricultural machines designed for collecting and compressing agricultural products such as forage or straw, in bales of various shapes and sizes.
The agricultural products thus compressed, having an appreciably lower volume, are more manageable, and this enables their easier transport and more convenient storage, and more generally a simple management, for various purposes.
Among the various different types of machine that are covered by the above mentioned category, a role of undoubted importance is occupied by “round balers”, which produce cylindrical bales.
To ensure the maintenance of the configuration assumed by the agricultural products, and thus prevent the bale that has just been made from breaking up, balers are equipped with devices for wrapping and tying, which are capable of wrapping the bale with a polymeric film or a net and of tying it with twine.
More specifically, with regard to the wrapping, according to conventional methods round balers are provided at the front with a reel of film or net, arranged parallel to the ground and perpendicular to the advancement direction, from which an end flap of the material designed to wrap the bale is progressively unwound.
Precisely in order to unwind the flap, and bring it proximate to the bale that has just been formed (which is usually inside a specially adapted and equipped chamber, defined in the main body of the baler), in front of and parallel to the reel there is a rubberized roller, on the at least partially elastically deformable outer surface of which a counter-roller can abut, so as to be able to tension the flap of net or film, and, following the rotation of the roller, determine the unwinding thereof and the sending to the chamber.
At the chamber, the high centrifugal forces to which the flap is subjected, as a consequence of the rotation speed of the bale, determine the automatic wrapping of the bale.
Such implementation solution is not however devoid of drawbacks.
The need to have a roller (and a respective counter-roller, or another device capable of abutting against the roller, so as to ensure the tightening and unwinding of the flap), determines first of all an increase in encumbrances, which, when designing and dimensioning the machine, complicates the placement of the elements used for the tying operations with twine.
Furthermore, by virtue of the pressure exerted by the counter-roller, over time the roller tends to deform locally, thus compromising the optimal operation of the apparatus, and thus the correct wrapping of the bale.
Finally, it must be noted that the roller, and the other elements associated with it, determines significant increases in cost and structural complexity.